Re: Smoke 2 more



On Mon, 08 Oct 2007 21:35:09 -1000, TheMakuleGuy wrote:

Demonick wrote:
On Sun, 07 Oct 2007 10:00:36 -0700, Miss Elaine Eos wrote:


In article <p9k5juuudd14.1mmxtzj03uovd$.dlg@xxxxxxxxxx>,
Demonick <demonick@xxxxxxxxxxxx> wrote:


A wave building to 1700' as it encounters a continental or ringing shelf
counts in my mind as a 1700' wave.

How about a 20' wave at sea that builds to 35 as it encounters shallow
water that shoots stuff 1700' upslope? Does THAT count as a 1700' wave?


No, not to my mind. The wave is as high as it is when it encounters the
shoreline.


And that is certainly the case, a 20-foot tsunami isn't 20 feet in the
deep ocean... However, compared to the normal wind-generated ocean
swell, tsunami are huge - a normal wave will have a wavelength of 100
meters (more or less), a tsunami traveling through the ocean can have a
wavelength of 100 kilometers... There are several factors that cause a
wave - any wave - to build up and crest, as you mentioned earlier, the
slope of the bottom, but that topography also creates friction which
causes the front of the wave to slow down and the rear of the wave to
push forward and over... Now imagine a pulse of energy 50 to 60 miles
long approaching the shoreline at 400 mph... It doesn't just crest and
break, it begins to build and churn and then just roars in... With
those kinds of wavelengths, the crest won't pass the shoreline until the
front of the wave has moved inland... In the video clips of the Dec 26
tsunami you can see ocean recede (the trough at the front of the wave)
and the surge of the water after the initial hit as the entire wave
moves over the shoreline...

A tsunami caused by a landslide will generate the same magnitude of
energy in a sudden release... In Lituya, the landslide occurred within
the inlet and was focused on the opposite side of the bay... This clip
shows a water tank model of the landslide and tsunami, and the bay after
the tsunami...

http://www.youtube.com/watch?v=ne7RVmbYc0A

You can see the scouring that was caused by the main body of the
wave(s)... Scary stuff... Luckily, not a common occurrence... The
1960 tsunami was pretty nasty around here (I wasn't around for the April
Fool's Day '46 one)...

I think cigars are a much more fun topic... Smoked Fonseca Cubano
Limitada while writing this up...

How are those? Tonight I start my packing!

--
Demonick
.



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